What is the difference between a tractor engine and a car engine?


As we all know, tractors use diesel engines, just like most cars use gasoline engines. Diesel engines are used because of their ability to produce higher torque with less fuel. This is very important because most operations done with tractors require a lot of force to complete. Why does a tractor engine make a throbbing noise while a car engine is quiet? Apart from the sound difference when driving, what is the difference between a tractor engine and a car engine?


The horsepower of a tractor is different from that of a car

The horsepower is perfect for acceleration that the tractor doesn't need. While tractors don't travel very fast, I think they probably have heavy-duty diesel engines designed to run somewhat continuously, as opposed to cars that are only used for very short maximum-rated power bursts. A heavy-duty engine used for generators or other equipment has a lower power rating than a car engine because it must maintain its power rating for hours or days at a time.


Engines work differently

The tractor to load for diesel engine is compression combustion, piston, and piston handle thick and long, stroke is a very long, natural force. Because the travel is relatively long, the speed is relatively slow, but the service life of diesel cars is also much longer than that of gasoline cars, the main purpose of small cars is to speed, through the spark plug ignition, the piston stroke is short, the speed is naturally fast because the travel is short, the torque is naturally less, the reaction is not so strong.

However, whether the diesel engine or the gasoline engine will consider the balance of power and torque when designing, to see which piece of design is more focused.


The gearbox variable tooth ratio of a tractor is different from that of an automobile

Variable tooth ratio is different, the power output is different, the tractor does not pursue speed but the pursuit of large torque, and the car is the pursuit of torque and the pursuit of speed. Tractors don't need horsepower, they need torque. Check your torque numbers, they may be much larger than you think. Even large tractor-trailers don't have tremendous horsepower, but they do have tremendous torque.

Nowadays, cars are generally diesel turbocharged EFI, the engine sound is small and the horsepower is large, and the tractor is not turbocharged because the transmission ratio of the gearbox is low, so the general tractor is not turbocharged because the diesel engine itself is enough.


The engine structure used in tractors and cars is different

Most gasoline engines and tractors are diesel, and the advantages of diesel engines are simple structure, high thermal efficiency, and large torque. However, it is relatively heavy and noisy, and the power under the same volume weight is much lower than that of the gasoline engine, which is not suitable for running high-speed cars. The advantages of gasoline engines are relatively light, high speed, and large power in the same volume. Tractors because of the work needs, the transmission ratio is large, and the torque amplification ratio is higher, so it does not run fast, but it is strong.


Tractor engines and car engines rotate at different speeds

The diesel engine used in agricultural machinery and automobile diesel engine work principle is the same, the difference is that agricultural machinery mostly uses low and medium-speed diesel engines, and automobiles use high-speed gasoline engines. A cylinder diameter greater than the stroke is a high-speed diesel engine, cylinder diameter less than the stroke is a low-speed diesel engine.

For example, in the same series of diesel engines, agricultural machinery does not need high speed, only the torque is larger, then the diesel engine structure has made corresponding changes, and the crankshaft radius increased. Like the lever principle, after the radius is increased, the crankshaft torque will increase when the same force is applied to the crankshaft, but the distance is spent. Therefore, the corresponding piston stroke is also longer, and the corresponding cylinder liner and connecting rod are longer.

As the stroke increases, the speed naturally decreases. Therefore, agricultural diesel engines have high torque and low speed. Automotive diesel engines are the opposite: the requirements for large torque are not particularly high, and the requirements for speed are higher. So the car engine is almost 2800 RPM, and the agricultural diesel engine speed is about 2000 RPM.



The core difference between gasoline engines and diesel engines is that their combustion mode is completely different, gasoline engines are premixed flame propagation combustion, while diesel engines are mainly diffusion combustion. Because of the different combustion modes, the efficiency and pollutant emissions of gasoline and diesel engines will be very different. If you have any questions about this or you need products related to the engine, you can contact us.



Which is better, the tractor engine or the gasoline engine?

Depending on your usage, tractors are widely used for farming and grain transportation. It is characterized by small horsepower, heavy load, good climbing, durability, simple maintenance, and so on. The gasoline engine has high speed, good adaptability, smooth and soft work, easy to operate, lightweight, low noise, low cost, easy to start, and so on.


Relating reading: John Deere 850 tractor with Yanmar 3T80J engine


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